I have a custom DialogFragment that I'm using to capture user input that I will create a database entry with. I'm using EditText in an AlertDialog. I am trying to use a single activity for my application and the original tutorial I was studying was using multiple activities and intents but that seems outdated for most cases.
When I debug I find that the EditText is returning "" and is showing up as empty when I call TextUtils.isEmpty() in the MainActivity onDialogPositiveClick.
I've done a lot of combing through the forms here and I'm confused by:
1)many of the answers I find are in Java and not Kotlin
2)many mention onCreate but do not specify onCreateView vs. onCreateDialog or if there's just an onCreate that I need to override.
I have researched this and found answers that confuse me a bit about when and if I need to inflate the layout. This current itteration I didn't inflate it at all. I just set it in the AlertDialog builder.
Maybe it's the interface I'm not understanding. How am I supposed to pass information between the dialog and MainActivity? The interface seems to pass the dialog itself but I seem to be missing something when it comes to getting the EditText from the dialog.
My custom DialogFragment
class NewSongFragment : DialogFragment() {
lateinit var listener: NewSongListener
lateinit var editNewSong: EditText
lateinit var editBPM: EditText
interface NewSongListener {
fun onDialogPositiveClick(dialog: DialogFragment)
fun onDialogNegativeClick(dialog: DialogFragment)
}
/** The system calls this to get the DialogFragment's layout, regardless
of whether it's being displayed as a dialog or an embedded fragment. */
/*
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View {
// Inflate the layout to use as dialog or embedded fragment
return inflater.inflate(R.layout.fragment_new_song, container, false)
}
*/
// Override the Fragment.onAttach() method to instantiate the NoticeDialogListener
override fun onAttach(context: Context) {
super.onAttach(context)
// Verify that the host activity implements the callback interface
try {
// Instantiate the NoticeDialogListener so we can send events to the host
listener = context as NewSongListener
} catch (e: ClassCastException) {
// The activity doesn't implement the interface, throw exception
throw ClassCastException((context.toString() +
" must implement NewSongListener"))
}
}
override fun onCreateDialog(savedInstanceState: Bundle?): Dialog {
return activity?.let {
// Use the Builder class for convenient dialog construction
val builder = AlertDialog.Builder(it)
//add inflater
//val inflater = requireActivity().layoutInflater;
//val view = inflater.inflate(R.layout.fragment_new_song, null)
builder
.setView(R.layout.fragment_new_song)
.setCancelable(true)
.setNegativeButton(R.string.cancel,DialogInterface.OnClickListener { dialog, id ->
dialog?.cancel()
})
.setPositiveButton(R.string.button_save,
DialogInterface.OnClickListener {dialog, _ ->
listener.onDialogPositiveClick(this)
})
// Create the AlertDialog object and return it
builder.create()
} ?: throw IllegalStateException("Activity cannot be null")
}
}
My MainActivity
class MainActivity : AppCompatActivity(),NewSongFragment.NewSongListener {
private val songViewModel: SongViewModel by viewModels {
SongViewModelFactory((application as SongApplication).repository)
}
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
//create view
val recyclerView = findViewById<RecyclerView>(R.id.recycler_view)
val adapter = ItemAdapter(this,
ItemAdapter.OnClickListener { rating -> songViewModel.insertRating(rating) }
)
recyclerView.adapter = adapter
recyclerView.layoutManager = LinearLayoutManager(this)
//initialize data
songViewModel.allSongs.observe(this) { song ->
// Update the cached copy of the songs in the adapter.
song.let { adapter.submitList(it) }
}
// Use this setting to improve performance if you know that changes
// in content do not change the layout size of the RecyclerView
recyclerView.setHasFixedSize(true)
//add song button
val fab = findViewById<FloatingActionButton>(R.id.fab)
fab.setOnClickListener {
showNewSongDialog()
}
}
private fun showNewSongDialog() {
// Create an instance of the dialog fragment and show it
val dialog = NewSongFragment()
dialog.show(supportFragmentManager, "NewSongFragment")
}
override fun onDialogPositiveClick(dialog: DialogFragment) {
// User touched the dialog's positive button
val editNewSong = dialog.view?.findViewById<EditText>(R.id.newSongTitle)
val editBPM = dialog.view?.findViewById<EditText>(R.id.newSongBpm)
if(TextUtils.isEmpty(editNewSong?.text)){
}else{
val newSong = Song(editNewSong?.text.toString(),100)
songViewModel.insertSong(newSong)
val rating = Rating(System.currentTimeMillis(),newSong.songTitle, 50)
songViewModel.insertRating(rating)
}
}
override fun onDialogNegativeClick(dialog: DialogFragment) {
// User touched the dialog's negative button
}
}
